Electric plug



Feb. 17933- K. B. ROUDEBUSH ET AL.

ELECTRIC PLUG Fi led June 2, 1931 I I I l I I l l l I l I I l l l l II.

ATTORNEY.

Patented Feb. 28, 1933.

UNITED STATES PATENT OFFICE KENNETH B. RdUDEBUSH AND HENRY G. EILERS, OI CINCINNATI, OHIO.

ELECTRIC 1 mm Application filed June 2, 1931. Serial 110. 541,554.

This invention relates to electric plugs and more particularly to separable plugs or plugs consisting of a body member and cap member, the body member of which is adapted to be screwed into a socket and the cap member of which is frictionally held within the body member.

The principal object of our invention is to provide spring-pressed means for the cap 0 member which will automatically lock it upon the body member and in this way prevent accidental disengagement of the cap member from the body member.

Heretofore in separable two-part electric plugs such as are used at the endof electric sweeper cords, washing machine cords, lamp cords and like electrical appliances, the cap member is often accidentally removed from the body member due to a slight strain on the 0 cord and this is especially so in electrical appliances such as floor scrubbing and polishing machines where the cord is under considerable strain at all times due to the winding reel usually employed upon such machines. 'With an electric plug made in accordance with the present invention the danger or possibility of the cap becoming accidentally separated from the body member or the plate member of a floor or wall receptacle is entirely eliminated.

The invention consists in supplying the cap member with spring-pressed pivotally mounted levers, the lower end of which are supplied with a hook or projection adapted to engage with plates embedded in the body member, said hook and levers serving to normally hold the cap member in locked relation upon the body member or receptacle plate, as the case may be, and when it is desired to remove the cap member from the body member it is only necessary to press inwardly upon the spring-pressed levers to automatically disengage the-hooked end thereof from the platesin the body member.

Our invention further consists in the'construction, combination, location and. arrangement of parts, as will be hereinafter more fully set forth and finally claimed.

In the drawing:

Fig. 1 is an enlarged side elcvational View of an electric plug embodying the principles of our invention and shown partly in verti-v cal section with one of the spring pressed levers shown in the released position by dotted lines; Fig. 2 is a similar view on a reduced scale looking towards the edge of one of the spring-pressed levers; r Fig. 3 is an isometric view of the cap member detached from the body member;

Fig. 4. is an isometric view of thebody' member;

Fig. 5 is a plan view of a receptacle plate madde to receive the spring-pressed levers; an I Fig. 6 is a bottom view of the cap member. In the embodiment of our invention as illustrated and which shows a' preferred con- 1 struction we provide an electric plug composed of a cap member 1 and body member 2, made of insulating material, as clearly shown in the drawing.

Referring to the construction of the cap member, 3 and 4 represent the usual projecting prongs which are riveted or otherwise securely attached to the cap 1 at 5 and supplied with conductor retaining screws 6, as shown in Fig. 6. 7 represents a cored or bored hole extending through the cap mem-; ber 1 for the purpose of admitting the electrical conductors in the usual and wellknown manner.

At the outer end of the cap member 1 we prefer to supply an enlargement or knob 8 and reduce the neck 9, as shown in Fig. 1, the knob 8 being utilized for a double purpose which will be presently described. 10 and 11 designate spring-pressed levers and, as shown. the upper end of each lever is bent backwardly upon itself to form an integral- "ly attached spring portion 12, the levers being preferably made of spring brassor of. an cqulvalent material. The lower end of lever 10 is supplied with a hook or [)lOJBCtIOI] 13 and terminates in a rounded point 14 5 and the lower cndof lever 11 is provided with a like hook or projection 15 and also terminates in a rounded point 16. Lovers 10 and 11 are further provided with an inwardly disposed projection 17 suitably drilled to receive the pivot pins 18, which pins are inserted within holes drilled in the cap memher and retained therein by heading the ends thereof, as shown in Figs. 1, 2 and 3.

Referring next to the body member 2 and to Fig. l, 19 and 20 designate a pair of apertures of the usual construction for receiving the projecting prongs 3 and 4, respectively. 21 and 22 represent oppositely disposed slots cut in the side wall and top of said body 2, which slots are of a width suitable for freely receiving the lower end of the spring-pressed levers IO-and 11, respectively.

Referring again to Fig. 1, 28 and 24 designate horizontal plates embedded within the body 2 and passing through the slots 21 and 22, the purpose of the plates being to engage with the hooks or projections 13 and 15 of levers 10 and 11, respectively.

Assuming that the usual cord or electrical conductors are attached to the projecting prongs of end 4 by the screws 6-6 and that body 2 is separated from the cap but screwed within a socket of the usual construction, all that is necessary to lock the cap 1 upon the body 2 is to insert the prongs3 and t within the apertures 19'a'nd 20 and press-inwardly, in the usual manner, whereupon the pointed ends 14 and 16 of levers 10 and 11 will ride over the plates 23 and 24, respectively, until the top faces of hooks or projections 13 and 15 pass beneath the bottom surface of said plates at which time the spring portions 12 of the levers will force. said hooks beneath said plates to substantially lock the cap 1 upon the body 2.

\Vith the cap 1 thus locked upon the body 2 any strain upon the conductors or cord of the cap will not disengage it from the body member. However, when it is desired to disengage the cap 1 from the body 2, it is merely necessary to grasp the upper end of levers 10 and 11 and press inwardly, thus compressing the spring portions 12, as shown by dotted lines in Fig. 1, and allowing the levers to pivot upon the pins 1818 to such an ex apertures 30 for receiving the levers 10 and 11. In this way a cap. supplied with levers 10 and 11 can be accommodated to thus-lock it upon said plate 28, as will be readily understood to those skilled in the art.

While we have shown and described one particular embodiment of our invention, it is to be understood that various changes and modifications can be made without departing from the scope or spirit thereof, the invention being limited only to the claims. I

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

A two-part electric plug comprising a cap having slots in the side wall thereof, an enlarged hand-knob formed integral with said cap, a pair of oppositely disposed levers received within said slots and pivoted to said cap, spring members formed integral with each lever and adapted to normally force the lower ends of said levers towards each other, an inwardly projecting hook formed at the lower end of each lever, a'body member having a pair of slots in its side wall to receive the lower end of said levers, and plates embedded within said body member and intersecting said last-mentioned slots, respectively, to engage with said hooks to releasably lock said cap upon said body.

KENNETH B. ROUDEBUSH. HENRY G. EILERS.

tent as to disengage the hooks 13-15 from i the plates 23 and 24. While pressing inward ly upon the upper end of the levers to disengage the hooked portion thereof, a firm grip can be had upon the neck 9 of the cap 1 by means of knob 8, thus eliminating any strain or stress upon the conductors in removing the cap from the body. The slots 25 and 26 out within the cap lare of a sufficient depth to receive the levers, the levers being pressed against the rear Wall 27 by the spring por tions 12 when the cap 1 is disengaged from the body 2 so it will, therefore, be seen that the wall 27 serves as a stop or limit for the in:

ward movement of said levers.

In order to make the cap 1 universal, we show, in Fig. 5, a usual receptacle plate 28 provided with the spaced apertures 29 and in addition to these apertures 29 we supply 

